Overload arrangement for mining planer



y 8, 1962 w ROSLER 3,033,542

OVERLOAD ARRANGEMENT FOR MINING PLANER Filed Aug. 6, 1958 2 Sheets-Sheet1 Fig./

INVEN TOR A/YULFF K SLER United States Patent 3,033,542 OVERLOADARRANGEMENT FOR MINING PLANER Wulif Rosier, Altlunen, Germany, assiguorto' Gewerltschfit Eisenhutte Westfalia, Wethmar, near Lunen', Westfalen,Germany, a corporation of Germany Filed An 6, 1958, Stet. No. 753,5tl6 1Claim. (Cl. 262-) This invention relates to a safety device arangementfor apparatus. More particularly, the invention relates to a safetydevice, such as for example a shear pin, interposed between a drive unitand a driven unit in such location and manner that it is readilyaccessible.

In order to establish an upper limit for the forces acting from thedrive on a mining machine, such as long face mining planets, whichinclude a plow and a conveyor, it is known to provide a safety coupling.The so-ca-lled shear pin safety device is very widely used. The purposeof such break type safety device consists inter alia in preventing thetransmission of excessively large forces to the traction means of themining machine, as might be the case for instance when the latter isblocked. in such a case, if there is no mechanism provided, which by itsown breaking interupts the drive, there would be the danger that thetraction means of the mining machine would be damaged by the drivingforces. Conditions are similar in the case of conveyors, such asdouble-chain scraper conveyors, the chains of which can jam or beotherwise blocked. In this case, also, the purpose of the safety deviceby its own breaking is to prevent the transmission of excessively largeforces.

In the known plow drives, the shear pin is generally arranged in thechain connected to the plow or else in the plow itself. In the lattercase, the plow operator must locate, i.e., uncover the plow member incase the shear pin breaks. With the enormous wall lengths customarytoday, this may be very difficult and time consuming. Furthermore, theplow in such case must be freed from the coal on it so that theshear-pin can be rep-laced. This is furthermore diflicult also for thereason that the plow is located between'the coal face and the conveyor.The replacement of the shear pin by a new pin is somewhat simpler if theshear-pin is located between the sprocket wheel and the driving shaft.However, even in such case the repair is difficult inasmuch as the spaceavailable is very small. Since the mechanic can scarcely get between theface and the drive, the required work must be done from the rear of theconveyor and therefore over the conveyor. If the conveyor is to continueoperating, as is frequently necessary, this work is further-more alsovery dangerous.

The primary object of the present invention is to develop and arrangethe safety device means, such as a shear-pin, for the driving of a coalplow or a conveyor in such a manner that replacement can be effectedwithout difficulty, rapidly and in particular without danger ofaccident.

The manner in which this and other objects are attained according to theinvention will be apparent from the following description with referenceto the accompanying drawings wherein an embodiment of the invention isset forth.

In the drawings:

PEG. 1 is a top view of a portion of a double-chain scraper conveyorwith the plow guided thereon and of the units for effecting the drive ofthe conveyor and plow; and

FlG. 2 shows a part of the gearing in open condition, partially insection.

The invention provides a mining tool including as operating units a coalplow and a conveyor. One or each 3,033,542 Fatented May 8, 1962 ice ofthe operating units includes a power receiving means which is linked todrive means by power transmitting.

means. The drive means and the power transmitting means are positionedon the side of the conveyor opposite the plow. The device according tothe invention is characterized in that power transmitting means is.connected to power receiving means by a safety device means, such asforexample a shear-pin, which is adapted to fail upon the load thereonbecoming excessive and thereby disconnect power receiving means fromdrive means. The safety device is positioned on the drive means side ofthe conveyor and hence is readily accessible.

In the embodiment shown in the drawing, the mining tool includes a plow15 and a conveyor 11. A guide track 7 is disposed along side theconveyor and serves to guide the plow 15 over a working courseparalleling the guide track 7 and also paralleling the mine working face20. The conveyor 11 is disposed adjacent and along side the workingcourse and is adapted to receive and carry away from the plow materialextracted by the plow from the working face.

Drive means for the plow 15 in the form of a motor 17 is operativelyconnected to the plow through powercan be moved along the working courseby the drive means.

The conveyor 11 includes chains 10 which have connected thereto atspaced intervals along the length of the conveyor the scraper bars 9.The conveyor chains 10 are mounted in the chain sprocket wheels 33 and33a of-the conveyor drive drum 14. Drive means in the form of a motor 12is operatively connected tothe conveyor drive drum through the powertransmitting means 6, and the coupling 21.

According to the invention, the linkage between the plow and its drivemeans, or the linkage between the conveyor and its drive means, or both,includes a safety device such as a shear-pin, which upon either theoperating unit becoming overloaded, will fail and thus disconnect theoverloaded unit from its drive means.

In FIG. 2 of the drawing, there is shown interconnection, according tothe invention between the conveyor 11 and its drive means 17. As shownin the drawing, the conveyor drive drum 14 has secured thereto conveyorsprocket wheel 33, which in turn is secured to a power receiving shaft24. Disposed coaxially about the power receiving shaft 24, on the end ofthe shaft 24 remote from the conveyor drive drum 14 and from the miningtool plow 15, is a hollow shaft 30 which functions as a powertransmitting shaft and is operatively connected to the motor 17 by agear train which includes spur gear 28 keyed to the hollow shaft by key28a, spur gear 27 which is fixedly mounted on drive means countershaft25, and the spur gear 26 operatively interposed between the countershaft25 and the main drive shaft (not shown) of the motor 17. The gear trainand power transmitting shaft are disposed in gear housing 13.

According to the invention, the power transmitting means, which includesthe said gear train and the hollow shaft 30, is connected to the powerreceiving means of the conveyor by a safety device disposed in a readilyaccessible location such as on the side of the gear housing 13 remotefrom the conveyor 11 and plow 15. In the embodiment shown in thedrawing, there is fixedly secured to the hollow shaft 30 by radiallyextending flange Ella, an outer sleeve 37, and there is fixedly securedto the power receiving shaft 24 an inner sleeve 38, and the Q inner andouter sleeves are connected by a shear-pin 31. The shear-pin 31 isprovided with a score line 13a whereby it is conditioned to fail uponthe load thereon becoming excessive. In consequence of failure of theshearpin, the drive means and' the power receiving means of the conveyorbecome disconnected whereby the load on the drive motor 17 is released.

Considering how details of the construction shown in the drawing, thechain sprocket wheel 33 is secured to the conveyor drive drum 14 bybolting 41, and the power receiving shaft 24 is secured to the chainsprocket wheel 33 by bolting 43. The power receiving shaft 24 is mountedin ball and socket roller bearings 44 and 45, the outer races of whichare secured to the gear housing 13. Inner bushing 34 and outer bushing35 are mounted on the power receiving shaft 24 and are interposedbetween the power receiving shaft and the hollow power transmittingshaft 30.

Connection between the inner sleeve 38 and the power receiving shaft 24is provided by acollar 48, which is coaxially received by the endportion of the power receiving shaft 24 and is keyed to the powerreceiving shaft 24 through keyway 49, and radially extending flange 32,which is formed integrally with the sleeve 38 and the collar 43.

Labyrinth seals 36 and 36a are provided, respectively, between the gearhousing and radially extending flange 30a, and between the radiallyextending flange 30a and the radially extending flange 32. An oil wayconnecting with seal 36a is provided in the radially extending flange30a. A labyrinth seal 51 is also provided between the sprocket chainwheel 33 and the gear housing 13. This seal includes a seal ring 52secured to the gear housing 13 by bolting 53.

The drive means countershaft 25 is mounted in ball and socket bearings55 and 56 and in roller bearings 58 and 59.

It will be apparent from the accompanying drawings that the inventionprovides means for interposing a safety device in a connection between amining tool drive means and ope-rating unit. The arrangement can includea power receiving shaft connected to the operating unit and a powertransmitting shaft connected to the drive means. One of the shafts hasan axially extending opening and receives coaxially in said opening aportion of the other of said shafts, and the shafts can be connected bythe safety device which is of such construction that it fails upon theload thereon becoming excessive. Whereas in the embodiment shown in thedrawing, the preferred construction is shown, wherein the powertransmitting shaft is a hollow shaft and is disposed over the powerreceiving 5:5. shaft, if desired, the power receiving shaft can be madehollow and the power transmitting shaft disposed coaxially within thepower receiving shaft.

While either or both of the operating units can be connected with its ortheir drive means by a safety device according to the invention, it isparticularly desirable to interconnect the plow and its drive means by asafety device according to the invention. This is so because in thecourse of mining operations, the plow frequently becomes overloaded sothat the safety device is frequently called into service.

I claim:

In a drive unit for a mining planer provided with a mining plow movableback and forth along a longitudinally extending conveyor, the drive unitincluding trans mission gear reduction means, a housing therefor, and

a sprocket wheel for a drive chain, the improvement which comprises saidsprocket wheel being mounted on an end of a drive shaft rotatablymounted within said transmission housing and extending transverselythrough the housing, the other end of said drive shaft extending to therear side of the conveyor and having connected thereto a disc with asleeve-shaped flange facing in the direction away from said sprocketwheel, a second disc with a sleeve-shaped flange concentricallypositioned with respect to said first mentioned disc and facing in thesame direction, said discs and flange-shaped sleeves being dimensionedto provide a free open space within the sleeve-shaped flange of theinnermost disc, said second disc being rotatably mounted within saidhousing, said second disc being d-rivingly connected to said gearreduction means, and a shear pin extending radially through saidsleeve-shaped flanges connecting the same for rotation together. i

References Cited in the file of this patent UNITED STATES PATENTS292,095 Carlson Jan. 15, 1884 881,075 Hosking Mar. 3, 1908 1,918,677Wingquist July 18, 1933 2,739,463 Pfister et al Mar. 27, 1956 2,853,893Magnuson Sept. 30, 1958 FOREIGN PATENTS 59,752 France Feb. 17, 1954(Addition to 1,005,173)

OTHER REFERENCES Coal Age, November 1950, page 92.

